Gear operated ratchet wrench



March 1, 1955 c MARVIN GEAR OPERATED RATCHET WRENCH 3 Sheets-Sheet 1 Filed Feb. 13 1951 I l l ll,

March 1955 c. -H. MARVIN 2,703,030

GEAR OPERATED RATCHET WRENCH Filed Feb. 13. 1951 3 Sheets-Sheet 2 //Il e/I/'0/' 8 6'. Hayes Marv/)7 March 1, 1955 c. H. MARVIN 2,703,030

GEAR OPERATED RATCHET WRENCH Filed Feb. 13. 1951 3 Sheets-Sheet 3 Divan/0r L; f/ayes fiarV/n FIG. /3

United States Patent GEAR OPERATED RATCHET WRENCH Charles Hayes Marvin, Lancaster, Calif., assignor to The Stead Rail Anchor Company Limited, Montreal, Quebec, Canada, a corporation of Canada This invention relates to improvements in wrenches and the object of the invention is to provide a ratchet type wrench having in addition to the usual ratchet drive,

a second higher speed drive which may be used during the greater part of the operations of applying or removing a nut or cap screw, leaving only the final tightening and the initial loosening to be performed using the ratchet drive. A further object is to provide a twospeed wrench, as aforesaid, so constructed that the change from ratchet drive to high speed drive, or vice versa, may be very easily and quickly efiected. A still further object is to provide a wrench, as aforesaid, of compact design and rugged construction which may be produced at reasonable cost. Various other objects and the advantages of the invention may be ascertained from the following description and the accompanying drawings.

In many types of machinery, access to nuts and cap screws or other threaded fastenings' which must be adjusted or removed and replaced from time to time is so seriously restricted that movement of, a wrench handle is limited to a small angle, often less than 60, and necessitates repeated shifting of a wrench to a fresh grip on,

the nut or screw, or the use of a ratchet type wrench.

In either case, the operation of applying or removing a nut or screw is tedious and consumes much valuable time. The wrench of my invention enables avoidance of these conditions and provides for rapid and easy application and removal of nuts and cap screws even under the aforesaid adverse conditions.

Broadly speaking, the invention consists in the combination of a handle carrying a rotatably mounted nutturning member, a ratchet driving connection between. the handle and said member and a geared drlvingrneans.

for said member adapted to rotate the same. at materially higher speed than is feasible through the ratchet driving means.

In greater detail, the invention consists in the features and combinations of features herein disclosed, together with all such modifications thereof and substitutions of equivalents therefor as are within the scope of the ap-' pended claims.

In the accompanying drawings which illustrate two embodiments of the invention and modifications thereof, but to the details of any of which the invention is not limited:

Fig. 1 is a longitudinal sectional view of a wrench embodying a bevel gear drive, showing the parts in position for high speed application or removal of a free turning nut or cap screw.

Fig. 2 is a view similar toFig. 1, showing the parts 0 in position for use of the ratchet drive in the final tightening or initial loosening of a nut or cap screw.

Fig. 3 is a plan view of the outer sideof the head end of the Wrench of Figs. 1 and 2.

Fig. 4 is a partial plan view of the inner side ofthe handle end of the wrench of Figs. 1 and 2.

Fig. 5 is a cross-sectional view of the wrench handle 1 at the. line 55 of Fig. 2..

Fig. 5 is a longitudinal sectional view of a wrench embodymg a worm gear drive, showing the parts in position for high speed application or removal of a freeturning nut or cap screw.

ing or initial loosening of a nut or cap screw. 1

Patented Mar. 1, 1955 Fig. 9 is a cross-sectional view of the head end of the wrench at the line 9-9 of Fig. 6.

Fig. 10 is a partial longitudinal sectional view illustrating a modified form of high speed drive and showing the parts in position for operation of the drive.

Fig. 11 is a view similar to Fig. 10, showing the parts. in position for use of the ratchet drive.

Fig. 12 is a partial longitudinal sectional view illustrating the application of a motor drive to the wrenches. of either of the embodiments of Figs. 1 to 9.

Fig. 13 is a fragmentary view of the under side of the handle of Fig. 12, showing the slot thereof.

Referring more particularly to the drawings and especially to Figs. 1 to 5 thereof, 21 designates a hollow wrench head having a removable cover plate 22 let into the head and preferably of irregular perimeter, whereby it cannot be assembled to the head otherwise than in predetermined position, and 23 designates a handle of any suitable form projecting from the head. As new preferred, the handle is of the tubular form illustrated and is strengthened by a pair of substantially parallel ribs 24 extending from the head to the free end of the handle.

A nut turning member 25 is rotatably mounted in the wall of the head and extends outwardly of the head. The member 25 is axially normal to the handle but, if

.desired, the angle between the handle axis and the axis responding to the member 24 and a socket member. The

member 25 may be provided in its squared portion with a spring pressed ball or bullet type latch 27 of usual or any suitable type for releasably holding socket or other members as above described. For convenience, the member 25 will be hereafter termed stub or stub member. Within the head 21, the stub is formed with an encircling row of teeth 28 of any suitable form, for example such as are customarily used in ratchet type wrenches. A reversible, or double ended pawl 29, also of any suitable or conventional type, is revolubly mounted in the head 21 in position for engagement of either of its ends with the ratchet teeth 28 and is provided with a positioning lever 30 fixed thereto externally of the head, and with a spring pressed ball, or bullet, type latch 31 mounted in the head and engageable in either of two recesses 32 to releasably hold the pawl with either of its ends positioned for engagement with the ratchet teeth 28. The pawl is further illustrated in Figs. 6 and 7. The stub may be provided with a steadying extension 33 rotatably mounted in a recess of the cover plate 22 which nected to the stub within the head 21, either by formation integrally with the stub, as shown, or in any other. suitable manner. The other gear, 35, of the pair ,is irrevolubly mounted on the end of shaft 36 which extends through the handle 23, and is mounted in bearings 37.,

and 38 which are slidable in the handle, in the longi-Q tudinal direction thereof. An antifriction washer or. a ball bearing, indicated at 39, is interposed between the hub of the gear 35 and the bearing 37. Any suitable means is provided tourge the bearing 37, shaft.36 and.

gear 35 to movement such as will mesh the gear 35 with f.

Fig. 8 is a plan view of the upper side jof thehead end of the wrench of Figs. 6 and 7, as viewed in these Figs; g-,projecting into the path of h bearing the gear 34 and for this purpose a helical spring 40 surrounding the shaft and in compression between the bearing 37 and an abutment 41 within the handle is now preferred. Any suitable stop means may be provided to limitmovement of the bearing 37 and prevent undue pressure of the gear 35 on the gear 34, the means now preferredbeing .a=snap ring .42 let into the head 21 on the opposite'side'of the bearing 37 from the spring 40farid The outer end of the shaft 36 is pivotally connected to a link 43 which is, in turn, pivotally connected to one end of a crank 44, at the opposite end of which is a pivotally mounted handle 45 adapted to be folded into a recess 46 in the crank. The link 43: is of angular form, as clearly shown, whereby its pivotal connection with the crank may be so disposed as to permit folding the crank along the handle, as shown in Fig; 2, where it ishoused between the ribs 24 and may be releasably held by any suitable form of latch, for example, a sliding, spring pressed latch 47 mounted on the handle between the ribs 24. The free end of the crank and the pivoted end of the handle 45 are provided with latch engaging shoulders 48 whereby the latch 47 serves both to hold the crank housed between the handle ribs and to hold the handle 45 housed in the crank recess. It will be observed by comparing the positions of the crank and link as shown in Fig. l with the positions shown in Fig; 2, that as the crank is swung toward the handle 23 it fulcrums against the end of the handle to draw the link 43 and shaft 36 outwardly of the handle, against the action of the spring 40, thereby to disengage the gear 35 from the gear 34; and that when the crank is. unlatched, the spring 40 tends to return the parts to the positions of Fig. 1. The angular form and the dimensions of the link 43 are such that when the crank is folded against the handle, the link has bearing against the end of the handle, normal to the axis of the handle, and the pivotal connection of the link and crank is disposed outwardly of the bearing point, whereby action of the spring 40 has little or no tendency to swing the crank out of its folded position and there is little or no stress on the atch.

Referring, now, to Figs. 6 to 9 of the drawings, the structure therein illustrated is, in general, the same as that illustrated in Figs. 1 to 5, the chief difference being in the form of the gears. In Figs. 6 to 9, 21 designates a hollow wrench head having a removable cover plate 22" let into the head and 23 designates a handle of any suitable form, connected to the head strengthened by ribs 24, as in the previously described embodiment.

A stub member 25 is rotatably mounted in the wall of the. head and extends inwardly and outwardly thereof, the outer part of the stub preferably being squared, as and for the purposes already described in connection with Figs. 1 to 5. Associated with the stub 25' is a. double ended or reversible pawl 29, such as already described, rotatably mounted in the head and having positioning means 30 external of the head. The stub may have a steadying extension 33 rotatably engaged in the cover plate 22.

A worm wheel 34 is fixedly connected to the stub within the head. The pawl 29 may be positioned to engagev directly with the teeth of the worm wheel, as shown, but, if desired, special teeth may be provided on the stub for engagement by the pawl, as in the embodiment of Figs. 1 to 5. A worm 35 is irrevolubly mounted on one end of the shaft 36, which extends through the handle 23 and is mounted in bearings 37' and 38. In this embodiment, the bearing 37 is located in the head and takes the form of a yoke spanning the worm, longitudinally thereof, and slidable between parallel guiding surfaces 37 formed in the head and inclined to the axis of' the shaft 36' in such direction and to such extent as. is necessary to move the worm into or out of mesh with the. worm wheel 34' when the. bearing and shaft are moved in the longitudinal direction of the shaft. The bearing 38 is rockable in the handle to accommodate itself to changes in shaft position occasioned by movement.

of the bearing 37 along its inclined guiding. surfaces, and is also slidable longitudinally in the handle. The. aforesaid changes in shaft position will cause a very slight rocking of the bearing 37 in its guides and the bearing should be a sufii'ciently loose fit in the guides. to permit of this rocking; or the guide engaging surfaces of the bearing may be slightly curved. Any suitable means, such as a helical spring surrounding the shaft and in compression between the bearing 37' and an abutment 41 in the handle, is provided to urge the bearing'37, shaft 36, and worm 35 to movement such as' will mesh the worm with the worm wheel.

As in the previously described embodiment, a link 43 connects the outer end of the shaftv to. a crank 44 having a pivoted handle 45; the. crank being adapted to be-folded against the handle 23, between the ribs 24 and to be retained in its folded position by a latch 47; the movement of the crank to its folded position serving to draw the shaft 36', bearing 37' and worm 35 toward the free end of the handle, against the urge of the spring 40, to disengage the worm from the worm wheel.

The operation of the wrench is the same in both of the embodiments described. To apply a nut, the pawl 29 is adjusted to proper position by means of the lever 30 and the wrench, with its parts in the positions of Fig. l or Fig. 6,, is. addressed to a nut. The crank 44 is turned torotate: the shaft and, through the medium of the gears, to rotate the stub 25. or 25' and the nut until the nut reaches the 'position for final tightening. The crank is then folded against the handle, as shown in Figs. 2 and 7, to unmesh the gears and. the handle is then oscillated about the axis of the stub in the manner usual in operation of ratchet wrenches, the pawl 29 serving to move the stub with the handle during handle movement in one direction and allowing the handle to swing around the stub during handle movement in the opposite direction. To remove a nut, the pawl 29 is appropriately adjusted and, with the parts in the position of Fig. 2 or of Fig. 7, the Wrench is applied to a nut and the handle is oscillated until the nut is loosened. The crank is then unlatched and swung out to operative position, enabling the spring to meshthe gears, and is rotated in the unscrewing direction of the nut to rotate the shaft, gears, stub and nut.

With gears of 1:1 ratio, as shown in Figs. 1 and 2, or even with lower ratio, as with the worm gearing of Figs. 6 and 7, it is obvious that a nut may be turned on oroff its bolt very rapidly and certainly much more rapidly than would be possible using an ordinary ratchet wrench. The adjustment of the wrench to change from gear drive to ratchet drive, or vice versa, may be accomplished" in an instant of time and without removing the wrench from the nut with which it is engaged. Owing to the leverage afforded by the crank, especially if the gear ratiov is less than 1:1, nuts which are somewhat tight on their bolts may be turned with substantially the same case and celerity as those which are a normal easy running fit. As the amount of power required to be transmitted through the gears is very little, they may be quite small; in fact, smaller in proportion to other parts of the wrench than they are shown in the drawings. By making the bevel gears of 1:2 or 1:3 ratio, or even lower ratio, the gear 35 may be proportionately smaller than shown and thus enable the wrench head to be quite thin, the advantage of which will be usually greater than any disadvantage resulting from lower nut turning speed. The gearing illustrated is such that the crank and the nut turn in the same direction but it will be obvious that the gearing may be otherwise arranged.

In Figs. 10 and 11 there is illustrated a modification applicable to either the bevel gear or the worm gear driven embodiments of the invention, which modification eliminates the operative feature of meshing and unmeshing gears when changing from gear drive to ratchet drive, or vice versa, and therefore enables elimination of provision for shifting gears.

In this modification, a wrench body, the head end of which may be constructed according to either of the previously described embodiments but is not shown, includes a handle 23" and a shaft 36 rotatable but longitudinally immovable in the handle, which shaft drives gearing and a stub (not shown) similar to those already described; The shaft projects beyond the end of the handle 23" and has pivoted to it one end of a short, cylindrical crank core. 51, upon which the hollow cylindrical end of a crank 52 is revolubly mounted and is retained by any suitable. means, such as a snap ring 53 seated in the crank and overhanging a shoulder of the core. A crank handle 54- is pivotally mounted at one end to the free end of the crank and is adapted to be folded into a recess of the crank. The end portion of the crank which surrounds the core and the free end portion of the wrench handle 23" are preferably of equal diameters and the handle 23" is provided with a sleeve 55 slidable therealong and over the said end portion of the crank when the latter is aligned with the shaft, as shown in Fig. 11, so as to hold the crank in this alignment and constitute it an extension of the wrench handle. The amplitude of sleeve movement is determined by stop shoulders 56 on the handle 23" and on the crank. Any suitable means,

such as a ball orbullet type latch 57,- maybe provided to releasably hold the sleeve in its extended position.-

To use the wrench as a ratchet wrench, the crank is aligned with the shaft and is so held by moving the sleeve into encircling engagement with the crank. Rotation of the stub in the wrench head during ratcheting'rotates the shaft gear and shaft in an integrating manner, this rotation being permitted by rotation of the crank core 51 within the end of the crank. To use .the wrench as a geared wrench, the sleeve 55 is retracted along the handle 23", thus releasing the crank which is swung to an operative position, approximately at right angles to the shaft, as shown in Fig. 10. This modification has the advantage that, in addition to eliminating the means. for shifting gears, the crank constitutes an extension of the handle affording greater leverage.

Fig. 12 illustrates the application of an electric motor to replace the crank 44 of the embodiments of the invention previously described, in so far as the crank serves to rotate a nut; and also illustrates mechanism to replace the crank in so far as it serves to mesh and unmesh the gears of the said embodiments. In other respects the motor driven wrench of this modification is constructed as shown in Figs. 1 to 5 or in Figs. 6 to 9. Because of the small amount of power required to operate wrenches as already described, especially if the gear ratio thereof is less than 1:1, it is possible to use a motor so small that it may be installed in a housing small enough to be conveniently grasped in the hand of the wrench operator. In this modification, an enlargement 61 of the wrench handle contains a small diameter, reversible motor 62, the stator of which is rigidly connected to the sliding shaft bearing 38, the bearing being, for the purposes of this modification, irrevolubly mounted in the handle. The motor rotor is connected to the shaft 36 or 36 in any suitable way, for example, through a friction clutch and a speed reduction gearing indicated at 63. An electric conductor 64 leads into the end of the handle portion 61 and, through a reversing switch 65, to the motor. Any suitable means is provided to serve the function of the crank 44 in retracting the shaft 36 or 36 against the spring to unmesh the gears. One such means comprises a collar 66 fixed to the shaft within the handle and a loose sleeve 67 surrounding the shaft between the collar and the gear meshing spring, and normally bearing against the collar. A lug 68 projects radially from the sleeve through a slot 69 in the handle, between the ribs 24, and has pivoted to it a finger piece 70 which may be folded against the handle, between the ribs, and may be swung out through an angle of approximately 90 to abut against a stop 71 on the lug, for use in retracting the shaft. The slot has a lateral extension 72 into which the lug may be moved to hold it and the shaft in retracted position, one end of the slot extension being undercut, as at 73, to receive the lug and hold it against accidental displacement from the slot extension.

In the operation of applying a nut, the gears being in mesh, as shown in either of Figs. 1 and 6, the motor is started in the appropriate direction and rotates the mechanism and nut until resistance of the nut to further rotation causes the clutch to slip. The shaft is then retracted by means of the finger piece 70, which is finally moved laterally to enter the lug into the slot extension 72 where it is held by the tension of the spring while the tool is being used as a ratchet wrench. To remove a nut, the tool is used as a ratchet wrench, its gears being unmeshed, until the nut is loosened. The spring is released by retracting the finger piece 70 to disengage the lug from the undercut 73 and the ing is moved laterally out of the slot extension 72 and is released to permit the spring to mesh the gears. The motor is then started in the appropriate direction.

While a motor drive is applicable to both the bevel gear and the worm gear embodiments of the invention, it is more useful in the worm geared embodiment, where the gear ratio may be quite low and manual operation by means of a crank would be correspondingly slow. The motor drive is particularly advantageous in wrenches used on an assembly line, where even small time saving in each operation becomes important. While a hand crank and an electric motor have been disclosed to rotate the shaft, it will be understood that other manual means or some othertype of motor may be used for the same purpose.

- Having thus described'my invention, I claim: V 1. In a wrench, a body, a nut turning stub and a shaft, both rotatably mounted in the body, gears operatively connecting the stub and the shaft, a shaft rotating crank pivotally related to one end of the shaft and foldable beside the body when not in use, and a latch carried by the body adapted to releasably hold the crank foldedbeside the body.

2. In a wrench according to claim 1, a handle pivoted to the free end of the crank and foldable beside the crank, said handle being adapted, when folded beside the crank and the crank beside the body, for holding engagement by said latch to retain the handle folded beside the crank. m i

3. In a wrench, a body, a nut turning stub and a shaft both rotatably mounted in the body, gears operatively connecting the stub and the shaft, a link pivoted at one end to one end of the shaft and adapted to fulcrum on the body, and a crank pivoted at one end to the other end of said link, and adapted to rock said link for movement of the shaft in its longitudinal direction.

4. A wrench comprising a body including a head and a handle rigidly connected to the head, a nut turning stub rotatably mounted in the head, a ratchet driving connection between the head and the stub, a shaft rotatably mounted in the handle, gears operatively connecting the shaft and the stub, and a crank pivotally connected to the shaft for rotating the same, said crank including two relatively revoluble parts, one of which is pivoted to the shaft, and means for releasably holding the crank in axial alignment with the shaft, whereby the shaft may be rotated while the crank is stationary.

5. A Wrench comprising a body including a head and a handle rigidly connected to the head, a nut turning stub rotatably mounted in the head, a ratchet driving connection between the head and the stub, a shaft, guiding surfaces in the head inclined to the axis of the shaft, bearings rotatably mounting the shaft in the handle, said bearings being slidably mounted in the body and one of them engaging said guiding surfaces, a gear rigidly connected to the stub to rotate the stub and a mating gear irrevolubly mounted on the shaft, a spring acting on said second gear to urge it into mesh with the stub gear, and means connected to that end of the shaft remote from the gears for rotating said shaft, and means for retracting said second gear against the urge of said spring to disengage the gears.

6. A wrench comprising a body including a head and a handle rigidly connected to the head; a nut turning stub rotatably mounted in the head; a ratchet driving connection between the head and the stub; a shaft disposed lengthwise of the handle and rotatably mounted therein; a worm Wheel fixed to the stub; a worm irrevolubly mounted on one end of said shaft to mesh with the worm wheel; a slidably mounted bearing for said shaft adjacent the Worm; guiding surfaces for said hearing formed in the head and so inclined to the axis of the shaft that reciprocation of the bearing along said surfaces will move the shaft laterally thereof toward and away from the worm wheel, with meshing and unmeshing the Worm and worm wheel; a bearing for the opposite end of the shaft oscillatably mounting the shaft in the handle; means urging said first bearing to such position as will mesh the worm and worm Wheel; means for retracting said bearing against the urge of said urging means and for holding the same retracted; and means to rotate said shaft.

7. A wrench comprising a body including a head and a handle rigidly connected to the head; a nut turning stub rotatably mounted in the head; a ratchet driving connection between the head and the stub; a shaft disposed lengthwise of the handle and rotatably mounted therein; a worm wheel fixed to the stub; a worm irrevolubly mounted on one end of said shaft to mesh with the worm wheel; a bearing for said shaft embracing said worm endwise thereof; guiding surfaces for said bearing formed in the head and so inclined relatively to the axis of the shaft that reciprocation of the bearing along said guiding surfaces will move the shaft laterally thereof toward and away from the Worm wheel, with meshing and unmeshing of the worm and worm wheel; a spring urging said bearing to position the worm in mesh With the Worm wheel; means for retracting said bearing against the urge of the spring; and means to rotate said shaft.

8. A wrench comprising a body including a head and a handle rigidly connected to the head; a nut turning stub rotatably' mounted in the head; a ratchet driving connection between the head and the stub;- a worm wheel fixed to said stub; a worm meshing with said worm wheel; a bearing movable in the head inwhich the worm is revolubly mounted; guiding surfaces in the. head' supporting said bearing for movement toward and away from the worm wheel; aspring urging said bearing to movement such as will mesh the worm with the worm wheel; means for rotating the worm; means for moving said bearing to unmesh the worm from the worm wheel; and means for holding the worm out of mesh with the worm wheel.

573,732 Warn Dec. 29, 1 896 Anspach Dec. 3, Van Wie Mar. 30, Kientz Nov. 8, Strickling; Apr. 21, Walton Aug. 21, Riemke Aug. 24, Hawk Feb. 15, Seaquist Fish Dec. 18, Shaif Oct. 21, Shaif Oct. 21,

FOREIGN PATENTS France May 6, Sweden Jan. 8, France Nov. 29, 

